Corrugator



Feb. 9, 1943. H. B. GREENWOOD CORRUGAT'OR 'Fil ed Sept. 1, 1939 2 Sheets-Sheet 1 gwuwwkw Hcnr B.Grecnw0od M 1269 Feb. 9, 1943. H. B. GREENWOOD 2 Sheets-Sheet 2 CORRUGATOR Filed Sept. lI 1939 a T m m T I? Hem" Teena/00d.

HEB STATES CORRUGATOR Henry B. Greenwood, Glen Arm, Md, assignor to F. X. Hooper Company, Inc., Glen Arm, Md, a corporation of Maryland Application September 1, 1939, Serial No. 292,994

6 Claims.

In the majority, if not all, of the existing corrugating machines for making single or double faced corrugated board, the top corrugator roller is grooved circumferentially to admit the strippers, and the adhesive for the liner facing sheets of the single board or the first facing sheet of the double board is applied to the corrugated web at the peaks of the corrugations before it leaves the bottom corrugating roller and this facing sheet or liner is applied to the corrugated web by means of a presser roller while the corrugated web is still on the bottom roller. In corrugating thin or porous webs of which latter kraft paper is a good example, some of the adhesive which is generally sodium silicate or t i f un 0 Examination of the Product water glass, is forced through the paper at, the made when these accumulations have formed on point of application of pressure by the presser the peaks of the teeth of the bottom corrugator roller. Most of this is removed from the bottom roller that these accumulations apparently not corrugator roller by the web being corrugated as only puncture the corrugated Web forming'a seeach particular tooth of the corrugator roller on ries of indentations or holes, as already pointed which the adhesive has been deposited performs out, arranged in lines extending in the direction its next corrugating operation, i. e., when it next of the length of the web and spaced in correpasses through the corrugating area where the spondence with the spa O the r ppe teeth of the top and bottom rollers cooperate in r ve in e p roller, b also apparently napplying corrugating pressure to the paper; dent theiacing web or liner which is applied un- It has been found, however, that the pressure tier p s u by the pressure olle and thfi'ad' applied by the top corrugating roller to the paper hesive apparently leaks through these points and by the paper to the teeth of the bottom coremph iz ng n m n m n p us he rugating roller is almost completely relaxed in disfigure 0f the P t Which is a so Weakthe zones in which the circumferential groovesin erred by the defect. the top roller previously mentioned as provided The object of the invention is to avoid and to admit the strippers between the web and the eliminate the defects in the product above dotop corrugator roll, register with the teeth of the nn'eor and to'avoid the loss of time of the machine bottom corrugating roller. Consequently, the and operator incident to cleaning the said alc portion f adhesive p i e n t pe s of he 5 cuinuiations of adhesive from tnebottoiii roller teeth of the bottom corrugating roller' in the areas of said peaks in which they register with said grooves is not removed by the paper during corrugating, and tends to build upas the operation of the machine progresses after cleaning. This accumulation of adhesive is probably combined with oil from the lubricating system and possibly with alum from the paper forming hard knots or convex protuberances which increase in their radial extent as the operation continues. These knots or accumulations ofadhesive after a short period of operation become sufficient in height or extent radially of the roller to indent the paper forming parallel lines of indentations in the corrugated web extending in the direction of the length of the web. These lines correspond in 1ateral spacing to the spacing ofthe stripper grooves in the top corrugating roller and the indentations are located in the peaks of the corrugations in the web which correspond to the peaks of the teeth of the bottom corrugator roll. These indentations tend to become deeper as the operation of the machine proceeds and the accumulation increases and eventually they become sufficient in extent radially of the roller to cut'through the paper forming the Web 7 Under any circumstances; it is necessary to stop' the machine at frequent" intervals when using the permeable papers described to clean'the adhesive from the bottom corrugating roller to prevent disfigurement of the corrugated board and in all instances the board is weakened to'a considerable degree as the accumulations become sufficient to iorm sizable indentations;

and stopping the machine for this purpose.

tion to the rotating motion whereby the registra' tion 01' the grooves being continually change'clthe accumulations of adhesive are eliminated'by close contact with the paper in corrugating.

roller a; very slight reciprocation in the direction of its axis. This motion while it completely eliminates the accumulation of adhesive; all adhesive which reaches the roller being removed 'bythe' paper in the corrugating area, requires but a very short axial motion of one roller relatively to the other and preferably operates at a relatively low speed as compared to the rotary motion of the rollers performing in the form of the machine'shown, which isatpresent in use, but one cycle of reciprocation of 1 The desired result is accomplished by imparting to one or both of the rollers a newmotion in addia This is accomplished by applying to either corrugator' inches to approximately 300 feet linear motion of the corrugated web.

The reciprocation of the roller which, in accord with the present practice, is preferably the bottom roller on account of the difiiculty in moving the strippers, so changes at regular intervals and continuously the area or Zone on the bottom roller with which the circumferential grooves in the top roller register, that any adhesive which passes through the paper into contact with the teeth of the bottom roller is completely wiped from the latter at very short intervals in the corrugating operation. This keeps the bottom roller entirely clear of adhesive at all times during the operation thus leaving no apparent accumulation. The necessity for stopping the machine to clean the bottom rollers is thus avoided, and, at the same time, a corrugated web and a single faced corrugated board, which is entirely free of the defects referred to is produced.

In the accompanying drawings, I have illustrated so much of a single facer embodying the roller reciprocating feature of the invention as is necessary to a full comprehension of the manner of constructing, applying, operating and using this improvement. A single facer only is illustrated as the application of the second liner or facer is not in any way affected by the invention, however, the invention is equally applicable to the production of both single face and double face corrugated board.

In the drawings:

Fig. 1 is a fragmentary elevation of the opposite ends and bearings of the upper and lower corrugator rollers also showing the roller reciprocating device, the center portion being removed.

Fig. 2 is an elevation of the reciprocating device taken from the left of the same as seen in Fig; 1.

Fig. 3 is a fragmentary side elevation of a corrugator illustrating the corrugator rollers and the application thereto of the reciprocating device.

Fig. 4 is a plan view of a fragment of corrugated board illustrating the defects which it is the purpose of the invention to overcome, the first facing sheet or liner being turned back to show the defect in the underlying corrugated webs.

Referring to the drawings by numerals, each of which is used to indicate the same or similar parts in the different figures, and at present having particular reference to Fig. 3, showing the portion of a single face corrugated board machine to which the invention relates, the construction shown comprises a top corrugator roller l and a bottom corrugator roll 2 in the cooperating relation for corrugating a web 8. The construction also includes a trough or pot 4 for adhesive and rotating in the pot or trough 4 is a pickup adhesive roller 5. Cooperating with this roller to apply the adhesive to the corrugated web is an adhesive applying roller 6, commonly known as a paste roller, and this figure also shows a pressure roller 1 at the lower right opposite the paste roller 6. The presser roller I cooperates with the bottom corrugator roller 2 to press the liner or facing sheet I I into permanently attached relation to and with the corrugated web IO to complete the assembling of the single faced corrugated board.

The nine point material or any suitable mate rial of which kraft paper is a good example to be corrugated is shown in the form of web 8 which is led from the left at the top of Fig. 3 to the top tangent of the top corrugator roller I. The web 8 passes downwardly to the right about said roller to the corrugating area 9 and the rollers I and 2 cooperate in forming the web of material 8 into the corrugated web I0. Adhesive is applied to the peaks of the corrugations of this Web It while it is still on roller 2, by adhesive roller 6.

In the form of the invention shown, the facing sheet or liner in the form of web II is fed from the lower right in Fig. 3 to the bottom tangent of the pressure roll I by which it i applied to the corrugated web I [I by cooperation of the pressure roll I with the bottom corrugator roller 2. In other words, both the application of the adhesive to the peaks II) of corrugated web and the pressing of the facer liner II into close contact with the web are performed while the web is still on roller 2.

It is the purpose of the present invention to eliminate the harmful effect of the circumferential grooves I2 in the top corrugator roller I. Three grooves are more or less uniformly spaced along the roll in the direction of its length. Grooves I2 are provided to admit strippers I4 which enter these grooves between the web I0 and roller II, there being one stripper for each groove. Strippers I4 strip the corrugated web II] from the top roller immediately beyond the corrugating area causing it to leave the roller I and follow the corrugated surface of the roller 2 which rotates in a left handed or clockwise direction causing the corrugated web II] to move from the corrugating area to the pasting area passing in contact with the pasting roller 6.

From the point of application of the adhesive to the corrugated web II) by the roller 6 the web Ill passes into contact with the first facer or liner II which meets corrugated web II) in the pressure area between the presser roll I and the lower corrugator roll 2. At this point the first facing strip or liner II is attached completing the assembling of the single faced corrugated board I5.

The features and operation thus far described are well known in the art.

Fig. 4 illustrates the defect already discussed in a general way as due to the accumulation of small points or small protuberances of adhesive on the bottom corrugator roll 2. These points, not shown, are formed in a series of circumferential lines of points located on the peaks 2" of the teeth 2' of corrugator roller 2. This line of points or protuberances is formed between the pairs of dotted lines H in Fig. 1. These points or protuberances are understood to be formed in accordance with the principles already discussed, 1. e., when permeable material is being corrugated. When the corrugating operation is continued after sufiicient accumulation of the material forming the points or protuberances referred to, these points form in the peaks III of corrugated web I0 a series of indentations or perforations I8, Fig. 4, and when these accumulations become sufficient to project through and beyond the web, similarly arranged and located perforations or indentations I9, are formed in the outer facing strip or liner I I. These indentations or perforations I8 and I9 are arranged in lines according to the width and spacing of grooves I2 which determine the lines of protuberances or points between the pairs of lines I! shown in Fig. 1. These lines of perforations or indentations are indicated in Fig. 4 by reference character IT on the liner II and on the corrugated Web I0.

In the form of machine shown, the bottom corrugator roller 2 is driven by a train of gears 9 which is usual in such machines and partly illustrated in Fig. 1. The top corrugator roller I is driven by the intermeshing of the corrugating teeth I6 and 2 on the respective rollers I and 2.

In the form of the invention shown, the reciprocating motion results from the operation of a worm and wheel unit now to be described.

In Fig. l, which is the preferred form now in use the top corrugator roller I is held against longitudinal motion, in any suitable manner, as by a rotary and thrust bearing for the top roller shaft I9, the bearing being mounted in any suitable support as the side frames 2|. There is a bearing I9, of any suitable type for roller shaft I 9 at the other end of the roller I.

The bottom corrugator roller 2 is mounted to slide and rotate in a bearing 22 in the side frame 2| and the shaft 24 of the bottom roller 2 extends to the left away from the roller 2 beyond the rotary and slide bearing 22 as shown in Fig. 1 and near its end at the extreme left, it is provided with a worm 25, formed on a sleeve 26, see Fig. 2, secured to the reduced end 21 of said shaft 24 by means of a nut 28 and a key, 29' or in any suitable manner. This worm is located in a carrier 29 in which is also mounted a worm wheel 88 which meshes with and is driven by the worm 25 on the shaft 24. The worm wheel is mounted on a transverse shaft 3! which in turn is mounted in bearings 32 in the carrier 29.

This carrier is is provided with a rotary bearing 33 formed in the carrier and engaging the said shaft 24 between suitable abutments $4 and 35 on said shaft, which cause the shaft to slide with the carrier. In the form shown the abutment 3 is a shoulder formed on the shaft and abutment 35 is a ring encircling the shaft and held in its relation to the shaft by the end of worm sleeve 26. This carrier 29 is restrained against rotation and is guided in its motion in the direction of the axis of the shaft 24 by a guide bar 35 which in the form of the invention shown is seated in the side frame 2i at 3'! and engages a slide bearing 38 in the casting 29.

The shaft iii to which worm Wheel 30 is secured is provided with two crank pins 39 on opposite sides of the carrier 29. These crank pins are eccentrically located as to the axis of the worm wheel shaft 3|, the eccentricity of the pins being shown at 3 I Each of the crank pins 39 operates a link ii! which engages a corresponding crank pin 39 in and by a bearing 39' and the links d9 extend inwardly toward the rollers i and 2 being substantially horizontal in their mid position. The inner end of each link 40, i. e., the end toward the rollers I, 2, is provided with a bearing 4| which engages and rocks upon a wrist pin 52 mounted in stationary support 43, on the frame. These pin supports 43 in the construction shown are carried by studs 44 permanently seated in the side frame 2|. The double cranks and links prevents side thrust and may be referred to in the singular for convenience. In the arrangement shown the links 49 rock about the stationary axis of the pins 42 through substantially equal arcs on each side of the horizontal, this motion being imparted to the links 49 by the rotation of crank pins 49.

The carrier 29 guided by bar 36 and shaft 2 sliding in bearing 22 is reciprocated in the direction of the roller axis by the throw of cranks 3| Fig. 1, the operating force being the reaction ofthe thrust applied to the frame by links 49. The carrier 29 in turn operating through abutments 34 and 35 moves the shaft 24* and roller 2 in the direction of the shaft and roller axis by a distance equal to the throw of the crank pins 39.

As already pointed out, the rotary motion of the roller 2 is thus transformed into longitudinal reciprocating motion of said roller, the motion thus transmitted being greatly reduced by the worm and wheel. In the form of the invention. shown there is one cycle of reciprocation of the roller 2 in an axial direction to approximately 300 feet linear motion of the corrugated web giving with a crank a speed ratio of 1/2400: representative as a satisfactory effective ratio.

This ratio may be varied to a very considerable extent. It is of great importance, however, in View of the pressures transmitted and applied to the paper by the corrugating rolls in the corrugating operation that this longitudinal motion be reduced to the minimum avoiding the loss of power incident to rapid or extended reciprocation of one roller relative to the other which would result in an excessive lossv of economy.

The reciprocation of one corrugating roller in. the direction of the axis so changes the area or zone on the bottom roller with which the circumferential grooves I 2 in the top roller register in the corrugating operation that the adhesive which leaks through the paper into contact with the teeth of the bottom roller is completely wiped from the latter by the paper being corrugated giving no opportunity for the adhesive to dry or set thus keeping the bottom roll entirely clear of set adhesive and preventing the objectionable accumulation and formation of the. harmful protuberances above described.

In this way, the necessity for stopping the machine to clean the bottom roller is avoided, and at the same time the corrugated web formed. on the machine of any variety of material suitable to this purpose whether it be permeable by the adhesive or impermeable is entirely free of the indentations and perforations above described as resulting from these points or pro tuberances of accumulated adhesive on the corrugator teeth.

As the corrugated web is not perforated or indented there can be no weakening of either the liner or the corrugated web and no spotting of' the line with adhesive due to perforation.

I have thus described specifically and in detail a corrugating machine or so much of such a machine equipped with the roller reciprocating features of the invention as is necessary to a fullcomprehension of the method of constructing, applying and operating and using the invention, however, the specific terms herein are used in a descriptive rather than in a limiting sense, a considerable Variation of the construction proportions and arrangements being contemplated and the scope of the invention being defined in the claims. No claim is made to other features of the corrugator independently of the reciprocating mecha- IllSIIl.

What I claim as new and desire to secure by Letters Patent is:

1. In a corrugating machine, having a plurality of cooperating corrugator rollers, one of said rollers having peripherally arranged stripper grooves, and both said rollers having intermeshing longitudinally extending teeth at right angles to said stripper grooves, and automatic means for applying to one said corrugator roller a reciprocating motion in the direction of its axis and relatively to the other said roller whereby the area of registration of the grooves in the one roller, with the teeth of the other roller at the corrugating area is varied continuously and the accumulation of adhesive on the teeth of one said roller in the area registering with the said grooves in the other said roller is prevented, said means for applying a reciprocating motion comprising a reducing gear and a continuously running power actuated driving connection therefor.

2. In a corrugating machine having a plurality of rotary intermeshing toothed corrugating rollers and operating mechanism therefor causing said rollers to co-operate in the corrugation of a web passed between said rollers, one said roller having peripheral stripper grooves, said teeth being longitudinal and at right angles to said stripper grooves, of a reducing gear driven from the operating mechanism, reciprocating means driven from said reducing gear and operatively connected to one of said rollers to impart to said roller a reciprocating motion in the direction of its axis and relatively to the other said roller, said motion being relatively slow and slight as compared to the rotary motion of the rollers, thus changing the zones of registration of said grooves with the teeth of the other roller and preventing the accumulation of set adhesive in said zone on said teeth.

3. In a corrugating machine having a pair of corrugating rollers provided with intermeshing teeth extending longitudinally of said rollers, which teeth cooperate in the corrugation of a web passed through the area in which said teeth intermesh, of a Worm, means for rotating said worm at a speed corresponding to that of said rollers, a worm wheel driven by the worm, and means operated by said worm wheel and connected to one said roller imparting to said roller a reciprocating motion in the direction of its axis and relatively to the other said roller whereby the reciprocated roller performs a single cycle for each rotation of said worm wheel, one of said rollers having stripper grooves at right angles to said teeth and the said reciprocating motion corresponding in extent to the width of said grooves serving to change the area of the cooperating roller which registers with said grooves and to prevent accumulation of adhesive on the portion of the teeth of said latter roller which registers with the grooves in the other roller in the intermeshing area.

4. In a corrugating machine having cooperating intermeshing rotary corrugator rollers having longitudinally extending teeth for corrugating a paper web passed through the intermeshing area of said rollers, one of said rollers having circumferential stripper grooves; a worm formed on the shaft of one of said rollers, which roller is mounted to slide in the direction of its axis, a worm wheel operated by said worm, a crank which is relatively short as compared to the radius of the worm wheel, the crank being operatively connected to said worm wheel, a link operated by said crank and having a wrist pin with a, stationary axis, a carrier for the worm and worm wheel and crank mounted to move in the direction of the roller axi and connected to said latter roller to move the same in the direction of its axis impelled by the reaction of the thrust of the linkagainst its wrist pin, the other roller being relatively restrained against axial motion, whereby the worm wheel, the roller and its shaft are reciprocated in the direction of the roller axis, and the area of registration of the grooves on one roller with the teeth of the other roller is varied automatically throughout the corrugating operation.

5. In a corrugating machine having a pair of oo-operating intermeshing corrugating rollers with teeth extending in the direction of their axes, and one of said rollers having peripheral stripper grooves at right angles to said teeth, one of said rollers being mounted to slide and a reducing gear for transforming the rotary motion of the rollers into a reciprocating motion corresponding to the width of the grooves, and means for applying said reciprocating motion to move said sliding roller in the direction of its axis relatively to the other said roller, whereby the zones of registration of said stripper grooves with the teeth of the co-operating roller are varied in minute proportion to the speed of rotation of the rollers, and accumulation of adhesive in said zones is prevented.

6. In a corrugating machine having a pair of intermeshing rollers with teeth extending longitudinally of said rollers which cooperate in the corrugation of a paper Web passed through the intermeshing area of said rollers and means for driving said rollers in said operation, one of said rollers having circumferential stripper grooves at right angles to said teeth; means for changing continually throughout the operation of the machine the area of registration of the stripper grooves in one roller with the teeth of the other roller, said latter means comprising an automatic power driven slow motion device and a connection from said slow motion device to one of said rollers, said connection comprising a reciprocating device whereby said latter roller is reciprocated in the direction of its axis relatively to the other roller through a distance commensurate with the width of the grooves, at the rate of one complete reciprocation for approximately 300 feet of linear motion or the corrugated surface of the rollers, preventing accumulation of adhesive opposite the grooves.

HENRY B. GREENWOOD. 

